<!DOCTYPE html>
<html lang="en"  xmlns:th="http://www.thymeleaf.org" xmlns="http://www.w3.org/1999/html">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<span th:text="${msg}"></span>
<form action="/index/login" method="post">
    username: <input type="text" name="username"><br>
    password: <input type="text" name="password">
    <button type="submit">提交</button>
</form>
</body>
</html>